This application is based on and claims priority to Japanese Patent Application No. 2001-220119, filed on Jul. 19, 2001, and Japanese Patent Application No. 2002-083857, filed on Mar. 25, 2002, the contents of which are hereby expressly incorporated by reference.
1. Field of the Invention
The present invention relates generally to an inverter type generator using a compact, lightweight alternator configuration, and more particularly to an inverter type generator including a supplemental DC boosting circuit to supply additional DC current when a high load is present.
2. Brief Description of Related Art
Conventionally, engine driven generators are designed to be able to deliver a maximum possible power rating even if such power is not used or is only used for a temporary amount of time. As a result, typical engine driven generators incorporate high power engines to operate high capacity generating bodies, making the overall design large, uneconomical, and heavy.
Typically, such engine operated generator designs operate a generating body at a high speed where the generating body delivers its rated power output at all times, even though the rated power is not needed for most of the time. Such operation causes the engine to run at an unnecessarily high speed, causing unwanted noise, fuel consumption, increased exhaust emissions, and high operating temperatures.
Conventional engine operated generator designs that provide occasional high power outputs are heavy, loud, and too large. Such conventional high power generator designs fail to deliver operator friendly operation while providing adequate power when required by the operator. Therefore an operator friendly, lightweight, quiet, environmentally friendly engine operated generator design delivering adequate power is needed.
Compact, lightweight, quiet, economical, and environmentally friendly engine operated generators promote functionality, savings, and successful operation. Such improved designs however pose a challenge of providing adequate power when needed.
One aspect of a preferred embodiment of the present invention is a compact, lightweight engine operated generator incorporating a small engine, a reduced output generator, and a DC/DC converter to boost a battery""s voltage output to supply additional power when a high load is present. A reduced engine size and a smaller generator cause less heat to be generated and result in an overall compact, lightweight design.
Another aspect of a preferred embodiment of the present invention is the use of an economy switch to allow the operating engine to run at a decreased speed when a high load is not present to thereby provide less noise, improved fuel economy, and lower exhaust emissions.
Yet another aspect of a preferred embodiment of the present invention is the use of two batteries wired in series to provide a larger voltage to be available to the DC/DC converter, thereby allowing the DC/DC converter to be smaller and lighter, which lessens the overall weight and size of the generator.